The purpose of the research was to determine a relationship between two key design parameters of a reverse-kingpin skateboard truck and the resulting maximum traction between the wheels and pavement. A reverse kingpin style truck is characterized by a bolt (kingpin) that is positioned between the pivot of the truck and the axles, as opposed to a traditional skateboard truck which has the kingpin behind the axle. The latter is most commonly seen on short skateboards. The parameters evaluated were ride height (distance from axle to the bottom of the board), and rake (the amount the axles are offset from the axis of rotation, which is established by a line drawn from the center of the pivot through the midpoint between the bushings). An experimental apparatus w as designed to isolate these two parameters from characteristics that vary from one truck to the next.?
The simulation trucks were setup using different configurations of ride height and rake, and then tested by exerting a horizontal force to the deck (simulating a rigid longboard deck). A constant vertical force was applied to the edge of the deck to simulate loading that would exist during a turn. By recording the maximum horizontal force for each configuration, plots of traction as a function of ride height and rake could be generated to compare with the hypothesized model. The consistency of the platform on the testing apparatus was insufficient for engaging all four wheels simultaneously, and as a result, no useable data was observed. We conclude by presenting a set of future directions that will be pursued, including refinement of the testing apparatus platform and isolation of material properties of the wheels which may cover up findings.
About Evan Aamodt:
Evan is from Wyncote, PA, having graduated from Abington Friends School before attending Lehigh University as part of the class of 2013. He is enrolled in the Integrated Business & Engineering (IBE) honors program and is pursuing dual degrees in Mechanical Engineering and IBE-Management with minors in Aerospace Engineering and Economics. Evanís interest in mechanical systems has been demonstrated by his extracurricular projects ranging from the development of a manual wheelchair built for his recently paralyzed mother, to the several longboard-related products which he is working to start a business around.